Electrochemical carbon dioxide/monoxide (CO2/CO) reduction is a potential candidate for sustainable energy conversion and storage. Copper (Cu)-based materials are the only catalysts capable of producing more reduced hydrocarbons and alcohols, yet the high overpotential and poor selectivity still remain a huge challenge, which require mechanistic insights into the reaction mechanism and active site identification. Here we present microkinetic studies for CO(2) reduction on different coppers facets with different terrace/step site ensembles based on energetics estimated from density functional theory (DFT) based models. Our microkinetic models unveils the key reaction steps and site identities that dictate the C1/C2/C3 and hydrocarbon/oxygenate selectivity. The simulation gives reasonable agreement with the experimental observation and provides some theoretical insights into the design principles of practical Cu and Cu-based catalysts under reaction conditions.
